Added lgamma_r and lgammaf_r

Author: ankane

src/math.rs

@@ -67,6 +67,8 @@ no_mangle! {
     fn ldexpf(f: f32, n: i32) -> f32;
     fn tgamma(x: f64) -> f64;
     fn tgammaf(x: f32) -> f32;
+    fn lgamma_r(x: f64) -> (f64, i32);
+    fn lgammaf_r(x: f32) -> (f32, i32);
     fn atan(x: f64) -> f64;
     fn atan2(x: f64, y: f64) -> f64;
     fn cosh(x: f64) -> f64;